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1.
检测分析技术是开展新污染物治理工作的基础,是精准识别新污染物的重要手段。本文对持久性有机污染物、内分泌干扰物、抗生素以及微塑料等四大类新污染物的检测方法进行了总结,并对检测分析方法进行了比较。提出了下一步做好新污染物检测工作要加强检测标准方法的顶层设计,开发高通量、效率高的检测方法,重视样品前处理技术的标准化研究和标准试剂的研发。  相似文献   

2.
蒸发光散射检测技术   总被引:33,自引:0,他引:33  
魏泱  丁明玉 《色谱》2000,18(5):398-401
 对高效液相色谱中的蒸发光散射检测技术进行了综述。重点介绍了蒸发光散射检测器的仪器构造、工作原理、影响检测的因素、检测理论及其在类酯、表面活性剂和药物成分等物质检测方面的应用。 关键词:蒸发光散射检测器;工作原理;检测理论;类酯;表面活性剂;药物  相似文献   

3.
研究了土壤或肥料检测实验室质量控制措施。从人员、设施和环境条件、设备、检测方法、方法验证、原始记录、检测报告、相关标准要求等方面对检测对象中包含“土壤或肥料”的实验室存在的问题进行了研究,从内部质量控制、能力验证活动等方面对质量控制实施情况进行了探讨。建议实验室质量控制活动中重视风险评估工作、进一步强化方法验证工作、认真核实检测报告。  相似文献   

4.
自"十三五"规划提出以来,国家对生态环境保护工作给予了高度重视,这给环境检测工作带来了巨大的机遇和挑战[1].实验室样品管理是环境检测工作的重要组成环节,也是实验室管理、实验室认可、计量认证的重要内容,更是检测结果公正性、科学性和准确性的重要保障[2].传统实验室在进行接样、暂存、流转、留样等样品管理全流程工作中需要大...  相似文献   

5.
杨冰仪  莫金垣  杨晓云  王立世 《色谱》1999,17(5):477-479
以碳糊电极作工作电极,采用高效毛细管电泳 安培法对感冒药中的扑尔敏、扑热息痛和维生素C的同时检测进行了研究。重点探讨了检测电位、缓冲溶液添加剂对分离检测的影响。结果表明,方法简便、灵敏,适合于常规分析。  相似文献   

6.
胶束电动毛细管色谱双通道电化学检测尼群地平   总被引:3,自引:0,他引:3  
创建了尼群地平的胶束电动毛细管色谱双通道电化学检测的分析新方法。采用 两台安培检测器并联构成双通道检测系统,采用单一碳糊工作电极,两台安培检测 器的检测电位分别设为+0.7V和-0.8V(vs.SCE)同,同时对尼群地平进行氧化和还原 测定,并实时对数据进行采集、处理,以图形方式显示。采用NH3-NH4Cl为背景电 解质,并加入十二烷基硫酸钠(SDS)和甲醇组成运行电泳介质,应用氧化、还原 双通道检测系统对尼群地平及其片剂进行了胶束电动毛细管色谱分离检测;对工作 电极的选择、电极电位的选择、SDS的浓度、甲醇浓度、运行缓冲溶液种类以及工 作电压和进样时间对分离检测的影响进行了研讨,取得满意结果。  相似文献   

7.
推导了高效毛细管电泳碳柱电极安培电化学检测的检测电流表达式,并以自制毛细管电泳/电化学检测系统对其进行了实验验证。对给定直径的工作电极,检测电流正比于碳柱工作电极插入检测毛细管长度的2/3次方,也正比于液体电渗平均体积流速的1/3次方。实验结果与公式吻合很好,说明了检测电流表达式的正确性。  相似文献   

8.
杨冰仪  莫金垣  赖容 《化学学报》2003,61(9):1461-1465
报道了一种双工作电极-双通道毛细管电泳电化学检测系统,实现电导和安培 同时检测或者安培与安培检测联用,使两种方法相互补充,发挥各自的优势。其中 ,工作电极与检测池的制作工艺简单,操作简便,通过不锈钢针管和毛细管作为套 管,无需三维微调装置即可简单实现双工作电极的准确放置及分离毛细管与工作电 极的准确对接,并根据分析体系的需要采用不同类型的工作电极和检测器;同时采 用复式滤波电路解决了不同检测器之间的电场叠加对输出信号的干扰问题。采用该 装置可以同时检测复杂体系中的电活性和惰性物质,或同时测定只能氧化或只能还 原的物质,还可以对具有氧化还原性质的物质进行纯度的确证。将该装置应用于实 际样品的测定,节约了分析时间,提高了分析速度,扩大了检测范围,结果令人满 意。  相似文献   

9.
采用硼掺杂金刚石(Boron-doped diamond,BDD)薄膜电极为工作电极,利用流动注射分析方法测定水体化学需氧量(COD),根据水样中有机物组分在工作电极表面氧化消耗的电量(Qoxidation)测定样品的COD值。考察了一些基本参数包括载液、工作电位、流速对检测信号的影响并选定了最佳检测条件。在最佳检测条件下,本法检测COD的线性范围为2.5~120 mg/L,检出限为1 mg/L。用该法测定化工厂和食品厂废水的COD值,相对标准偏差和回收率分别在2.4%~4.8%和96%~106%之间,且检测结果与国家标准方法(CODcr法)有良好的一致性。  相似文献   

10.
离子色谱法具有快速、方便、选择性好、灵敏度高和多组分可以同时分离等特点,近年来在文物保护方面得到一定的应用。对离子色谱法在文物有害盐的检测、脱盐工作评估及文物保存环境中有害气体检测方面的应用进行综述,阐明了离子色谱在文物保护工作中的重要作用。  相似文献   

11.
Multiconformation continuum electrostatics (MCCE) explores different conformational degrees of freedom in Monte Carlo calculations of protein residue and ligand pKas. Explicit changes in side chain conformations throughout a titration create a position dependent, heterogeneous dielectric response giving a more accurate picture of coupled ionization and position changes. The MCCE2 methods for choosing a group of input heavy atom and proton positions are described. The pKas calculated with different isosteric conformers, heavy atom rotamers and proton positions, with different degrees of optimization are tested against a curated group of 305 experimental pKas in 33 proteins. QUICK calculations, with rotation around Asn and Gln termini, sampling His tautomers and torsion minimum hydroxyls yield an RMSD of 1.34 with 84% of the errors being <1.5 pH units. FULL calculations adding heavy atom rotamers and side chain optimization yield an RMSD of 0.90 with 90% of the errors <1.5 pH unit. Good results are also found for pKas in the membrane protein bacteriorhodopsin. The inclusion of extra side chain positions distorts the dielectric boundary and also biases the calculated pKas by creating more neutral than ionized conformers. Methods for correcting these errors are introduced. Calculations are compared with multiple X‐ray and NMR derived structures in 36 soluble proteins. Calculations with X‐ray structures give significantly better pKas. Results with the default protein dielectric constant of 4 are as good as those using a value of 8. The MCCE2 program can be downloaded from http://www.sci.ccny.cuny.edu/~mcce . © 2009 Wiley Periodicals, Inc. J Comput Chem, 2009  相似文献   

12.
毛细管电泳电化学检测   总被引:8,自引:0,他引:8  
综述了毛细管电泳的电化学检测,包括电位法、电导法和安培法检测的研究进展,重点讨论了电化学检测与毛细管电泳的耦联,并对电化学检测的原理及其应用进行了较详细的叙述,引用文献72篇。  相似文献   

13.
A simple electrochemical method was developed for the single and simultaneous determination of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) in food samples using square-wave voltammetry (SWV). A carbon composite electrode modified (MCCE) with copper (II) phosphate immobilized in a polyester resin was proposed. The modified electrode allowed the detection of BHA and BHT at potentials lower than those observed at unmodified electrodes. A separation of about 430 mV between the peak oxidation potentials of BHA and BHT in binary mixtures was obtained. The calibration curves for the simultaneous determination of BHA and BHT demonstrated an excellent linear response in the range from 3.4 × 10−7 to 4.1 × 10−5 mol L−1 for both compounds. The detection limits for the simultaneous determination of BHA and BHT were 7.2 × 10−8 and 9.3 × 10−8 mol L−1, respectively. In addition, the stability and repeatability of the electrode were determined. The proposed method was successfully applied in the simultaneous determination of BHA and BHT in several food samples, and the results obtained were found to be similar to those obtained using the high performance liquid chromatography method with agreement at 95% confidence level.  相似文献   

14.
Nyholm L 《The Analyst》2005,130(5):599-605
During the last few years there has been a rapid increase in the use of electrochemical reactions in lab-on-a-chip devices. This development, which has so far mainly focussed on electrochemical detection in chip-based capillary electrophoresis, can be explained by the fact that electrochemical techniques and devices are particularly well-suited for inclusion in lab-on-a-chip systems. The most important reason for this is that the required electrodes can readily be manufactured and miniaturised without loss of analytical performance using conventional microfabrication methods. In this Research Highlight article, the developments during the last three years concerning electrochemical techniques for lab on-a-chip applications are discussed, with particular focus on emerging electrochemical methods for sample clean-up and preconcentration, electrochemical derivatisation and electrochemical detection in chip-based capillary electrophoresis.  相似文献   

15.
Carbon nanotubes (CNTs) have been incorporated in electrochemical sensors to decrease overpotential and improve sensitivity. In this review, we focus on recent literature that describes how CNT-based electrochemical sensors are being developed to detect neurotransmitters, proteins, small molecules such as glucose, and DNA. Different types of electrochemical methods are used in these sensors including direct electrochemical detection with amperometry or voltammetry, indirect detection of an oxidation product using enzyme sensors, and detection of conductivity changes using CNT-field effect transistors (FETs). Future challenges for the field include miniaturizing sensors, developing methods to use only a specific nanotube allotrope, and simplifying manufacturing.  相似文献   

16.
《Analytical letters》2012,45(1-3):258-270
The design and fabrication of a home-made thin-layer electrochemical flow cell are reported. The performance and electrochemical characteristics of thin-layer cells are evaluated in terms of flow rate and channel thickness. The adaptability of the flow cell for amperometric and electrochemiluminescence measurements is demonstrated. Also, a flow injection method comprising electrochemical generation followed by spectrophotometric detection is proposed for determination of bromide using the fabricated cell. The influence of chemical, electrochemical, and flow parameters on the absorbance and current signals are investigated, and under optimized conditions, the analytical features of the proposed method with respect to bromide detection are evaluated.  相似文献   

17.
监测肿瘤标志物水平变化是评估肿瘤治疗效果的重要方法.基于石墨烯复合材料构建的电化学免疫传感器可实现对肿瘤标志物的检测,检测灵敏度高、特异性好,是快速、准确分析肿瘤标志物含量的理想检测工具.本文重点阐述了石墨烯复合材料的电化学免疫传感器在肿瘤标志物检测中的应用进展.总结了其在肿瘤标志物检测中应用的优势和不足,最后对基于石...  相似文献   

18.
Recent years have provided numerous new examples of applying flow-through electrochemical detectors in chemical analysis. This review, based on about 250 original research papers cited from the current analytical literature, presents their application in flow analysis and capillary electrophoretic methods. Example applications are also given for arrays of electrochemical sensors in flow analysis and electrochemical detection in microfluidic systems. Potentiometric detection with ion-selective electrodes predominates in flow analysis carried out mostly in a flow-injection system, while amperometric and conductivity detections are most commonly employed in capillary electrophoresis.  相似文献   

19.
Determination of inorganic phosphate by electroanalytical methods: A review   总被引:1,自引:0,他引:1  
Determination of inorganic phosphate is of very high importance in environmental and health care applications. Hence knowledge of suitable analytical techniques available for phosphate sensing for different applications becomes essential. Electrochemical methods for determining inorganic phosphate have several advantages over other common techniques, including detection selectivity, stability and relative environmental insensitivity of electroactive labels. The different electrochemical sensing strategies adopted for the determination of phosphate using selective ionophores are discussed in this review. The various sensing strategies are classified based on the electrochemical detection techniques used viz., potentiometry, voltammetry, amperometry, unconventional electrochemical methods etc., The enzymatic sensing of phosphate coupled with electrochemical detection is also included. Various electroanalytical methods available in the literature are assessed for their merits in terms of selectivity, simplicity, miniaturisation, adaptability and suitability for field measurements.  相似文献   

20.
电化学免疫分析法研究进展   总被引:27,自引:8,他引:27  
焦奎  张敏 《分析化学》1995,23(10):1211-1217
电化学免疫分析法是将免疫分析与电化学分析技术相结合的一种免疫分析新方法,近十多年来,电化免疫分析的研究有了迅速的发展。本文对电化学的免疫分析法的标记物、免疫方法、电化学检测技术进行了概括总结,并展望了电化学免疫分析的发展前景。  相似文献   

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